Pulsed electro magnetic field therapy is a form of therapy that originated over 60yrs ago in human therapy for the healing of non union fractures and has been FDA approved for human use in bone healing, post surgical pain and healing and depression. PEMF systems are composed of coils of copper wire through which a current is delivered. The current is turned on and off repeatedly which is what makes it pulsed. As it’s turned on and off the magnetic field expands and collapses repeatedly and can cover quite a large area. It is most commonly used in a matt form the patient can lie on, and this has been recently transposed to a rug which we see in equine use. In human use there are a number of smaller machines that you can buy for home use which range from about $300-$1000, in horses there are many machines available marketed to be a business option and they range from $10k – $30k.
How does it work?
When our cells are healthy they contain both positive and negative charges which are required for efficient ion exchange and normal cell function (as ions are either positively or negatively charged). Under stress these cells lose their ability to function effectively. PEMF helps to restore cells to their natural state much the same as low level laser and red light therapy. Reducing pain and inflammation and increasing healing time.
Depending on the current applied, PEMF may relax capillary walls thereby boosting blood flow to the area. It can also impede electrochemical reactions in the cells though, interfering with their ability to transmit pain.
What makes different machines different?
PEMF machines work on different frequencies of electromagnetic waves and that’s what makes them all different. Different tissue types respond differently to different frequencies so you want to make sure you’re using the right frequency for the issue you’re treating.
A lot of the machines manufactured for human use only have the options for very low level electromagnetic fields, or only one setting.
For example Oxford medical horse blanket has a field strength of 20-66 microtesla with 8 copper coils. I couldt find any specifications for the equine units except to say the frequency was high. Most human PEMF machines operate 6-8 coils and under 100 microtesla which is equivalent to 1guass.
Some machines are so powerful though they although they may be effective in treating severe issues such as non union fractures, are they too strong to help with normal cell function? Unfortunately there is a lot of marketing available and very little research to make an educated opinion on this. It is also very difficult to find any specifications on machines available to purchase for equine use.
Is PEMF safe
Human research has all been on low level PEMF frequencies showing little side effects and good results. There can be a few side effects of using the therapy on an otherwise healthy body though and these include an increase in pain as well as oxidative stress. An increase in pain can occur when the nerve signals are increased through circulation enhancement, oxidative stress occurs when there are a large number of free radicals in the body brought in by the increase in blood flow, that the body doesn’t have the ability to detoxify. Other side effects that are documented are fatigue, dizziness, increased urination, fall in blood sugar, decreased blood pressure, tingling, sleep disturbances and more.
Lately though we have seen some very strong machines released in the equine world which rather then having a basis in science have been developed in the principle of if a low level field is effective then a large field is better. Unfortunately there is no science behind these and consequently they are a banned FEI therapy.
There are still a number of PEMF devices available for horse owners that operate using the weak field though, so if it is a therapy you want to utilise research your product thoroughly before purchase and don’t be swayed by marketing alone.